Question

Use elimination to solve each system.

A customer at a concession stand bought 2 boxes of popcorn and 3 drinks for $12. Another customer bought 3 boxes of popcorn and 5 drinks for $19. How much does a box of popcorn cost? How much does a drink cost?*
Please explain how you got the answer by showing steps.*

Answer 1

$3 and $2

Explanation:

let p represent popcorn and d drinks , then

2p + 3d = 12 → (1)

3p + 5d = 19 → (2)

multiplying (1) by 3 and (2) by - 2 and adding will eliminate p

6p + 9d = 36 → (3)

- 6p - 10d = - 38 → (4)

add (3) and (4) term by term to eliminate p

0 - d = - 2

- d = - 2 ( multiply both sides by - 1 )

d = 2

substitute d = 2 into either of the 2 equations and solve for p

substituting into (1)

2p + 3(2) = 12

2p + 6 = 12 ( subtract 6 from both sides )

2p = 6 ( divide both sides by 2 )

p = 3

Popcorn costs $3 and a drink costs $2